An anatomy guidebook for students or anyone who wants to learn more about what goes on in our shell. Which is rather interesting as colouring seems more like child play to some. I think it's a cool method to teach the learner subliminally without forcing too much into his or her head.
Colouring is an acknowledged form of therapy, although I'm not sure whether it is, scientifically. Colouring can help us to take our mind off our surroundings and immerse into a meditative and concentrated state which ultimately helps us to relax. When we're more relaxed, our mind becomes more inclined to absorb knowledge, therefore whatever we think it's just child play, could be subconsciously seared on the back of our minds. If only my history books came in pictures instead of text, I would have coloured every single thing and score with flying colours.
I wonder what else could we use this system for? I think primarily it will be highly beneficial for fields related to teaching and learning. Anything else?